Embodiments of the present invention generally relate to Radio Frequency Identification (RFID) applications. More specifically, embodiments of the present invention relate to techniques for tracking objects using key rotation.
Radio Frequency Identification (RFID) is an automatic identification method which relies on the storing and remotely retrieving of data using devices, such as RFID tags or transponders. RFID tags or transponders are also known as proximity, proxy, or contactless cards, because data from an RFID tag can be retrieved without physical contact. Generally, a device, such as an RFID reader, uses radio waves to remotely retrieve a unique identifier stored using the RFID tag when the RFID tag is within proximity of the RFID reader. RFID tags can be attached to or incorporated into a product, animal, or person for the purpose of identification by the RFID reader. RFID readers can be placed on doorways, in train cars, over freeways, mounted on vehicles, and also can be embodied in mobile handheld devices.
RFID technologies have been traditionally implemented in different ways by different manufacturers, although global standards are being developed. Thus, computer applications using RFID are also typically hard-coded to specific RFID devices sold by the same manufacture. One problem with this arrangement is that these computer applications have traditionally been limited to using only the sensor data retrieved from the vendor supplied RFID readers.
Moreover, in order to provide automated shipping and receiving, real-time inventory, automated shipping and received, and real-time security, other types of RFID sensor devices, such as environment sensors (e.g., temperature and humidity sensors), location sensors (e.g., Global Positioning System or GPS devices), and notification devices, may be required. Accordingly, with the addition of each sensor device, a specific application may be required to access the sensor data from the sensor device. This vendor lock-in leads to having too many non-integrated applications, creates unnecessary complexity, and also increases costs associated with the management and deployment of RFID technologies.
One solution is to embed the sensor device with the RFID tag. For example, one cold chain solution provides an RFID tag embedded with a temperature sensor. Cold chain refers to a temperature-controlled supply chain. An unbroken cold chain is an uninterrupted series of storage and distribution activities which maintain a given temperature range. A reader can read both the identifier of the RFID as well as the temperature from the embedded sensor.
However, by embedding sensors with RFID tags, the cost, and complexity associated with each RFID tag increase. Furthermore, computer applications configured to read the sensor data are still tied directly to specific RFID readers. Thus, the only items for which sensor data can be used from those applications are still those that can be tagged and directly sensed using the specific vendor supplied RFID readers.
Accordingly, what is desired are improved methods and apparatus for solving the problems discussed above, while reducing the drawbacks discussed above.